The NEI Central Transgenic Animal Facility is a research support facility for all NEI intramural researchers requiring the use of transgenic mice in their research programs. We are currently providing transgenic animal support to researchers from six laboratories in the NEI (LI, LMDB, LMOD, LRCMB, OGSCB, OSD); in our program, there are currently 171 DNA constructs which are at various stages of completion. NEI researchers, using molecular biology techniques to study the eye, submit DNA constructs to our section for production of transgenic mice. We create transgenic mice by standard procedures, then biopsy and perform DNA analysis on the mice which are born from these procedures to identify transgene positive mice. At the researchers' request, we mate positive transgenic mice, wean litters, biopsy and analyze DNA from successive generations of transgenic mice, provide the transgenic animals to researchers for use in their experiments, and cryopreserve and bank embryos from important mouse lines (both transgenic and naturally occurring) for long term storage. This year we have: * generated 58 transgenic founder mice from 15 DNA constructs; * set up 515 matings of transgenic mice weaned, tagged and tail biopsied 4,443 mice; * isolated DNA from 5,638 samples; performed 6,913 DNA analysis; * frozen 421 embryos to preserve 2 mouse lines. Since the program began in 1991 we have: * generated 882 transgenic founder mice from 171 DNA constructs; * set up 2,119 matings of transgenic mice; * weaned, tagged and tail biopsied 21,381 mice; * isolated DNA from 21,007 samples; performed 23,334 DNA analysis; * frozen 5,470 embryos to preserve 19 mouse lines.